@font-face{font-family:VT323;font-style:normal;font-weight:400;font-display:swap;src:url('/vt323.ttf') format('truetype');}500;600;700&family=Manrope:wght@400;500;600;700;800&display=swap');
:root{--ink:#172d2b;--muted:#6e7f7a;--green:#166555;--line:#e2e8df;--paper:#f8f9f4;--mint:#e8efe1}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:15px 'DM Sans',sans-serif}button,input,select{font:inherit}button,a,input,select{outline-offset:4px}button{cursor:pointer}a{color:var(--green)}aside{position:fixed;width:244px;height:100vh;padding:34px 24px;background:#fff;border-right:1px solid var(--line);display:flex;flex-direction:column}.brand{display:flex;align-items:center;gap:12px;font-size:28px;font-weight:700;text-decoration:none;color:var(--green);letter-spacing:-1.3px}.light{font-weight:400;color:var(--ink)}.eyebrow{font-size:9px;letter-spacing:1.3px;margin:20px 0 40px;color:var(--muted)}nav button{border:0;background:transparent;color:#586962;display:flex;align-items:center;gap:13px;text-align:left;width:100%;padding:13px 12px;margin:5px 0;border-radius:7px;font-size:13px}nav button.active{background:var(--mint);color:var(--green);font-weight:700}nav button span{font-size:19px;width:22px}.aside-bottom{margin-top:auto;font-size:11px;color:var(--muted)}small{display:block;font-size:10px;line-height:1.8;margin-top:18px}.status-dot{display:inline-block;width:6px;height:6px;background:#75a28a;border-radius:50%;margin-right:5px}.shell{margin-left:244px}header{height:87px;padding:0 45px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);font-size:10px;font-weight:700;letter-spacing:1.4px;background:#fff9}.slash{margin:0 15px;color:#acb5a9}header div{display:flex;gap:12px}input,select{border:1px solid var(--line);background:white;padding:10px 12px;border-radius:6px;color:var(--ink);font-size:12px}main{max-width:1320px;padding:45px;margin:auto}.kicker{font-size:10px;letter-spacing:2px;font-weight:700;color:var(--green)}h1,h2,h3{font-family:Manrope,sans-serif}h1{font-size:43px;letter-spacing:-1.8px;line-height:1.2;margin:16px 0}h2{font-size:23px;letter-spacing:-.6px}h3{font-size:17px}.subtitle{font-size:15px;color:var(--muted);line-height:1.8;max-width:570px}.hero{display:grid;grid-template-columns:1.5fr 1fr;gap:20px;padding-bottom:30px}.hero-art{position:relative;min-height:230px;display:grid;place-items:center}.hero-art svg{width:260px;max-width:100%;height:230px}.note{position:absolute;right:8%;bottom:10px;font-family:Georgia;font-style:italic;color:#718c72;font-size:16px}.primary{border:0;background:var(--green);color:#fff;border-radius:6px;padding:12px 18px;font-weight:600;font-size:12px}.secondary{border:1px solid #ccd7cb;background:white;color:var(--green);border-radius:6px;padding:10px 15px;font-size:12px}.hero .primary{margin-top:12px}.stats{display:grid;grid-template-columns:repeat(3,1fr);background:white;border:1px solid var(--line);border-radius:9px;margin-bottom:36px}.stat{padding:20px 26px;border-right:1px solid var(--line)}.stat:last-child{border:0}.stat b{font:700 25px Manrope;display:block}.stat span{font-size:11px;color:var(--muted)}.section-head{display:flex;align-items:center;justify-content:space-between;margin:24px 0 18px}.section-head h2{margin:0}.section-head span{font-size:11px;color:var(--muted)}.grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.card{background:#fff;border:1px solid var(--line);border-radius:9px;padding:25px;position:relative}.card:hover{border-color:#a7bfa5}.card-icon{width:43px;height:43px;border-radius:9px;display:grid;place-items:center;background:#eef2e8;color:var(--green);font:24px Georgia}.card p{color:var(--muted);font-size:12px;line-height:1.8;margin:8px 0 22px}.card h3{margin:17px 0 0}.card-bottom{border-top:1px solid var(--line);padding-top:15px;display:flex;justify-content:space-between;font-size:11px;color:var(--muted)}.card button{border:0;background:none;color:var(--green);font-weight:700;padding:0}.tag{font-size:10px;letter-spacing:.3px;background:#eef2e7;border-radius:4px;padding:5px 8px;color:var(--green)}.callout{background:#eaf0e4;border:1px solid #dce6d5;border-radius:7px;padding:20px 24px;line-height:1.8;margin:25px 0;font-size:13px}.lesson-row{display:flex;width:100%;align-items:center;gap:18px;text-align:left;background:white;border:1px solid var(--line);padding:19px 23px;margin:10px 0;border-radius:7px;color:var(--ink)}.lesson-row .num{font:16px Georgia;color:#9ba99a;width:28px}.lesson-row strong{display:block;font-size:14px}.lesson-row small{margin:5px 0 0;font-size:11px}.lesson-row .tag{margin-left:auto;white-space:nowrap}.reading{max-width:790px}.reading p,.reading li{line-height:1.95;font-size:15px}.formula{font:22px Georgia;padding:24px;background:#f0f3e9;border-radius:6px;margin:20px 0}.reading h2{margin-top:35px}.back{background:none;border:0;padding:0;color:var(--green);font-size:12px;margin-bottom:25px}.practice{border-top:1px solid var(--line);margin-top:38px;padding-top:15px}.question{background:white;padding:24px;border:1px solid var(--line);border-radius:8px;margin:16px 0}.question p{font-size:15px;line-height:1.8}.source{font-size:11px}.actions{display:flex;gap:9px;flex-wrap:wrap;margin-top:18px}.feedback{font-size:13px;line-height:1.8;margin-top:16px}.correct{color:#146243}.incorrect{color:#a74434}details{margin-top:18px;line-height:1.9;font-size:13px}summary{cursor:pointer;color:var(--green)}.empty{padding:30px;background:white;border:1px dashed #b7c7b4;border-radius:8px;line-height:1.8}.progressbar{height:4px;background:#e3e9de;border-radius:4px;margin-top:12px}.progressbar div{height:100%;background:var(--green);border-radius:4px}footer{margin:30px 45px;padding-top:20px;border-top:1px solid var(--line);display:flex;justify-content:space-between;font-size:10px;color:var(--muted)}.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0)}@media(min-width:1450px){main{padding:55px 65px}}@media(max-width:1000px){aside{width:200px;padding:28px 14px}.shell{margin-left:200px}header{padding:0 25px}main{padding:30px}header>span{display:none}}@media(max-width:700px){aside{position:static;width:100%;height:auto;padding:18px}aside .eyebrow,.aside-bottom{display:none}nav{display:flex;overflow:auto;margin-top:15px}nav button{width:auto;white-space:nowrap;padding:8px}nav button span{display:none}.shell{margin:0}header{height:auto;padding:15px;display:block}header div{width:100%}header input{min-width:0;flex:1}main{padding:25px 18px}.hero{grid-template-columns:1fr}.hero-art{display:none}h1{font-size:34px}.grid{grid-template-columns:1fr}.stat{padding:15px}.stat b{font-size:22px}footer{margin:20px}.lesson-row{padding:16px 12px;gap:8px}}

/* Night study room · Krillion's VT323 typeface */
:root{color-scheme:dark;--ink:#dbe9f4;--muted:#94a9bd;--green:#7fd8c7;--line:#263b50;--paper:#091321;--mint:#142e3b}body{font-family:'VT323',monospace;font-size:21px;background:radial-gradient(ellipse at 90% 0,#14283e 0,transparent 52%),var(--paper)}h1,h2,h3,.stat b{font-family:'VT323',monospace;font-weight:400}h1{font-size:54px;letter-spacing:0}h2{font-size:32px;letter-spacing:0}h3{font-size:27px}aside{background:#0c1929}.brand{font-size:32px;letter-spacing:1px;font-weight:400}.brand .light{color:#dbe9f4}.eyebrow{font-size:13px;letter-spacing:1px}header{background:#0c1929;font-size:15px;letter-spacing:1px}nav button{font-size:20px;color:#a8bed0}nav button.active{font-weight:400}input,select{background:#102237;border-color:#30475d;color:var(--ink);font-size:19px}.kicker{font-size:17px;letter-spacing:2px}.subtitle{font-size:23px;line-height:1.5}.primary{background:#7fd8c7;color:#091b26;font-size:20px;font-weight:400}.secondary{background:#102237;border-color:#38546a;color:#a9e5db;font-size:19px}.stats,.card,.lesson-row,.question,.empty{background:#0e1e30;border-color:var(--line)}.stat b{font-size:34px}.stat span{font-size:18px}.card-icon{background:#172f41}.card p{font-size:21px;line-height:1.45}.card-bottom,.section-head span{font-size:18px}.card button{font-size:20px;font-weight:400}.tag{background:#193543;color:#a5ddd1;font-size:16px}.callout{background:#112b38;border-color:#254654;font-size:21px;line-height:1.5}.lesson-row strong{font-size:22px;font-weight:400}.lesson-row small{font-size:17px}.lesson-row .num{color:#83a0b8}.reading{max-width:850px}.reading p,.reading li{font-size:23px;line-height:1.6}.formula{font-family:serif;font-size:19px;background:#10283a;padding:20px;overflow-x:auto;border:1px solid #244458}.formula mjx-container{margin:.4em 0!important}.reading mjx-container,.question mjx-container{font-size:85%!important;color:#e0f4f1}.question p{font-size:23px;line-height:1.6}.source,.back{font-size:18px}.feedback,details{font-size:21px;line-height:1.5}.correct{color:#85dfb7}.incorrect{color:#ffaca0}.aside-bottom{font-size:17px}small{font-size:16px}.progressbar{background:#22364a}.progressbar div{background:#78cebc}.hero-art svg{filter:brightness(.7) saturate(.7)}.note{color:#a0c1bc}.section-head{gap:15px}footer{font-size:17px}.resource-list{padding:0;list-style:none}.resource-list li{border-bottom:1px solid var(--line);padding:14px 0}.resource-list small{margin:3px 0;color:var(--muted);font-size:18px}.mindset{margin-top:32px;padding:24px;border:1px solid #355568;border-radius:8px;background:linear-gradient(135deg,#142d3c,#101f33)}.mindset h2{margin-top:0}.mindset li{margin:12px 0}blockquote{margin:28px 0 0;padding:20px 0 0;border-top:1px solid #355568;font-size:26px;line-height:1.4;color:#c2eee4}blockquote cite{display:block;font-style:normal;font-size:18px;color:var(--muted);margin-top:12px}.math-inline{white-space:normal}@media(max-width:700px){h1{font-size:42px}nav button{font-size:18px}.stat span{font-size:15px}.reading p,.reading li,.question p{font-size:22px}.brand{font-size:30px}.section-head{flex-wrap:wrap}.formula{font-size:16px}.lesson-row .tag{font-size:14px}.hero .subtitle{font-size:22px}}

.katex{font-size:1em;color:#e0f4f1}.katex-display{margin:.5em 0}.katex-error{color:#ffaca0!important}

button:disabled{opacity:.5;cursor:not-allowed}.streak-strip{display:flex;align-items:center;gap:24px;padding:16px 20px;border:1px solid #355568;background:#10283a;border-radius:8px;margin-bottom:32px;flex-wrap:wrap}.streak-strip .secondary{margin-left:auto}.account-panel{display:flex;align-items:center;justify-content:space-between;gap:20px;margin:24px 0;background:#102237;border:1px solid var(--line);border-radius:8px;padding:22px}.account-panel h2{margin:0}.account-panel p{font-size:19px;color:var(--muted)}.account-panel a{display:inline-block;text-decoration:none;margin-right:12px}.calendar-panel{background:#0e1e30;border:1px solid var(--line);border-radius:8px;padding:24px;margin:24px 0}.calendar-header{display:flex;align-items:center;justify-content:space-between}.calendar-grid{display:grid;grid-template-columns:repeat(7,minmax(0,1fr));gap:8px}.weekday{text-align:center;color:var(--muted);padding:8px}.calendar-day{min-height:76px;padding:12px;background:#102237;border:1px solid #263b50;border-radius:6px;color:var(--ink);font-size:23px;text-align:left}.calendar-day small{font-size:15px;margin:7px 0 0}.calendar-day.visited{background:#1c3c50}.calendar-day.studied{background:#24566a}.calendar-day.solved{background:#256c61}.calendar-day.today{border:2px solid #7fd8c7}.calendar-day.selected{outline:2px solid #c2eee4;outline-offset:2px}.calendar-legend{font-size:18px;color:var(--muted);display:flex;gap:16px;flex-wrap:wrap}.think-timer{margin:22px 0;padding:18px;background:#132d3c;border:1px solid #355568;border-radius:7px}.think-timer>div{display:flex;justify-content:space-between;gap:16px;margin-bottom:14px}.timer-clock{font-size:28px;color:#9ce6d5;font-variant-numeric:tabular-nums}.think-timer small{color:var(--muted);font-size:18px;line-height:1.5;margin-top:12px}.solution-lock{color:var(--muted);font-size:19px;margin-top:20px}nav button{padding-top:10px;padding-bottom:10px}aside .eyebrow{margin-bottom:24px}@media(max-width:700px){.calendar-panel{padding:10px}.calendar-grid{gap:4px}.calendar-day{min-height:60px;padding:6px;font-size:20px}.calendar-day small{font-size:12px}.account-panel{align-items:flex-start;flex-direction:column}.think-timer>div{flex-wrap:wrap}.streak-strip{gap:12px}.streak-strip .secondary{margin-left:0}}

.focus-settings{margin-top:24px}.todo-add{display:flex;gap:12px;margin:12px 0}.todo-add input{flex:1;min-width:0}.todo-list{padding:0;list-style:none}.todo-item{display:flex;align-items:center;justify-content:space-between;gap:12px;border-bottom:1px solid var(--line);padding:14px 0}.todo-item label{display:flex;align-items:flex-start;gap:12px;line-height:1.5;flex:1}.todo-item input{accent-color:#7fd8c7;width:20px;height:20px;margin-top:5px;flex-shrink:0}.todo-item.is-done span{text-decoration:line-through;color:var(--muted)}.fullscreen-option{display:block;margin:20px 0}.focus-large{font-size:60px;color:#a5eddf}.focus-exit{border:0;background:none;color:#a9bdcc;cursor:pointer;text-decoration:underline;font:18px VT323,monospace;padding:10px}.focus-feedback{color:#f3cc8d}#focus-banner{position:fixed;bottom:0;left:244px;right:0;z-index:30;background:#102f3d;border-top:2px solid #7fd8c7;display:flex;align-items:center;justify-content:center;gap:18px;padding:14px;flex-wrap:wrap;box-shadow:0 -8px 25px #0005}.focus-active .shell{padding-bottom:100px}#focus-decision{color:var(--ink);background:#0e2032;border:1px solid #79cbbd;border-radius:12px;padding:30px;max-width:650px;width:calc(100% - 30px);max-height:90vh;overflow:auto;font:22px VT323,monospace}#focus-decision::backdrop{background:#020a14d9}.resource-button{color:var(--green);background:none;border:0;text-align:left;padding:6px 0;font:20px VT323,monospace;cursor:pointer}#focus-decision h2{margin-top:0}#focus-decision small{color:var(--muted)}.focus-settings>input{margin-left:14px}@media(max-width:1000px){#focus-banner{left:200px}}@media(max-width:700px){#focus-banner{left:0;gap:6px;padding:8px;font-size:18px}.todo-add{flex-direction:column}.focus-active .shell{padding-bottom:150px}}

.resource-button{display:inline-block;text-decoration:underline;text-underline-offset:4px}.resource-button:hover{color:#c5fff2}.lesson-permalink{font-size:18px!important;margin:10px 0}.lesson-permalink a{font-size:18px}.copy-status{color:var(--muted)}.footer-links{display:flex;gap:18px;flex-wrap:wrap}.footer-links a{font-size:17px}footer{gap:20px;flex-wrap:wrap}#cookie-notice{position:fixed;bottom:18px;left:calc(244px + 20px);right:20px;z-index:100;display:flex;align-items:center;gap:24px;background:#112b3b;border:1px solid #629e98;border-radius:10px;padding:22px;box-shadow:0 8px 45px #0008;font-size:21px}#cookie-notice p{margin:8px 0;font-size:19px;line-height:1.4}#cookie-notice a{font-size:18px}.cookie-actions{display:flex;flex-direction:column;gap:8px;min-width:190px}body:has(#cookie-notice){padding-bottom:190px}.info-page h2{margin-top:30px}.info-page .card{margin:20px 0}@media(max-width:1000px){#cookie-notice{left:220px}}@media(max-width:700px){#cookie-notice{left:10px;right:10px;bottom:10px;flex-direction:column;gap:12px;padding:16px}.cookie-actions{width:100%;flex-direction:row;flex-wrap:wrap}.cookie-actions button{flex:1;white-space:nowrap;font-size:17px}body:has(#cookie-notice){padding-bottom:290px}.footer-links{gap:12px}}

.sigma-brand{flex-direction:column;align-items:flex-start;gap:10px;text-decoration:none}.sigma-equation{font-size:27px;line-height:1.7;white-space:nowrap}.sigma-equation .katex{font-size:1em}.brand-name{font:21px VT323,monospace;letter-spacing:2px}.sigma-brand+.eyebrow{margin-top:15px;font-size:11px}aside{overflow-y:auto}@media(max-width:700px){.sigma-brand{flex-direction:row;align-items:center;gap:18px}.sigma-equation{font-size:24px}.brand-name{font-size:20px}}

#account-chip{white-space:nowrap;text-decoration:none;font-size:17px;letter-spacing:0;padding:9px 12px}header>div{align-items:center}@media(max-width:700px){header>div{flex-wrap:wrap}#account-chip{font-size:16px}}

/* Keep the study menu reachable on shorter screens. */
aside{height:100vh;height:100dvh;overflow-y:auto;overflow-x:hidden;overscroll-behavior:contain;scrollbar-gutter:stable;scrollbar-width:thin;scrollbar-color:#507f85 #0c1929}aside>*{flex-shrink:0}aside::-webkit-scrollbar{width:8px}aside::-webkit-scrollbar-track{background:#0c1929}aside::-webkit-scrollbar-thumb{background:#507f85;border-radius:8px}#nav button[data-page="focus"]{border:1px solid #4f8c88;background:#163b47;color:#b3f4e7;margin-bottom:15px}#nav button[data-page="focus"].active{background:#236253}.home-focus{display:flex;align-items:center;gap:24px;border:1px solid #4d8983;border-radius:10px;background:linear-gradient(110deg,#153d48,#11283b);padding:25px;margin:0 0 32px}.home-focus-symbol{font-size:52px;color:#8be4d1}.home-focus h2{margin:6px 0;font-size:33px}.home-focus p{font-size:21px;line-height:1.4;margin:8px 0;color:#b8cedb}.home-focus-steps{font-size:18px;color:#91b9bf}.home-focus>.primary{margin-left:auto;white-space:nowrap;flex-shrink:0}@media(max-width:1000px){.home-focus{gap:16px;flex-wrap:wrap}.home-focus>.primary{margin-left:0}}@media(max-width:700px){aside{height:auto;max-height:340px;max-height:46dvh;overflow-y:auto}aside nav{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));overflow:visible;gap:4px}aside nav button{width:100%;white-space:normal}#nav button[data-page="focus"]{margin-bottom:5px;grid-column:1/-1}.home-focus{padding:20px;gap:12px}.home-focus-symbol{display:none}.home-focus h2{font-size:30px}.home-focus>.primary{width:100%}}

.why-section{margin:28px 0;padding:22px 26px;background:#112b38;border-left:3px solid #7fd8c7;border-radius:0 8px 8px 0}.why-section h2{margin:0 0 14px}.why-section p{margin:0}.why-section .katex{color:#d5f5ee}@media(max-width:700px){.why-section{padding:18px}}

.sigma-symbol{font:52px Georgia,serif;line-height:1;color:#a5edde}.sigma-brand{gap:10px}

.home-tao-quote{margin:0 0 32px;padding:25px 30px;background:#102b38;border:1px solid #335e65;border-left:4px solid #8ce1ce;border-radius:8px}.home-tao-quote blockquote{margin:0;padding:0;border:0;font-size:32px;line-height:1.4;color:#c6f1e6}.home-tao-quote figcaption{font-size:20px;color:#9ebbc8;margin-top:12px}.home-tao-quote figcaption a{font-size:17px;margin-left:16px}@media(max-width:700px){.home-tao-quote{padding:20px}.home-tao-quote blockquote{font-size:27px}.home-tao-quote figcaption a{display:block;margin:8px 0 0}}

.checklist-heading{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}.checklist-heading h2{margin:0}.checklist-help{color:#b2c7d4!important;margin:12px 0 20px!important}.todo-list .todo-item{background:#102638;border:1px solid #304b5d;border-radius:8px;padding:14px 16px;margin:10px 0}.todo-list .todo-item label{cursor:pointer;align-items:center;min-height:38px;font-size:23px}.todo-list .todo-item input[type=checkbox]{appearance:none;-webkit-appearance:none;display:grid;place-content:center;width:28px;height:28px;min-width:28px;margin:0;border:2px solid #86bdba;border-radius:5px;background:#071725;cursor:pointer;padding:0}.todo-list .todo-item input[type=checkbox]:checked{background:#83d9c3;border-color:#83d9c3}.todo-list .todo-item input[type=checkbox]:checked:after{content:"✓";color:#08222a;font:27px VT323,monospace;line-height:1}.todo-list .todo-item input[type=checkbox]:focus-visible{outline:3px solid #d1fff1;outline-offset:4px}.todo-list .todo-item.is-done{background:#12372f;border-color:#367967}.todo-list .todo-item.is-done span{color:#91bcb0;text-decoration-thickness:2px}.todo-list .todo-item .secondary{font-size:22px;padding:5px 10px}@media(max-width:700px){.todo-list .todo-item{padding:12px}.todo-list .todo-item label{font-size:22px}}

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